#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<math.h>
int main()
{
	int n,i,j,flag;
	while(~scanf("%d",&n))
	{
        int num[n][n];
        flag = 0;
        for ( i = 0; i < n; i++)
        for ( j = 0; j < n; j++)
            {
                scanf("%d", &num[i][j]);
                if(i>j&&num[i][j]==0)
                  flag = flag + 0;
                if(i>j&&num[i][j]!=0)
                  flag = flag + 1;
            }
        if(flag==0)
            printf("It is up\n");
        else
            printf("up false\n");
    }
	return 0;
}
